According to Mass account creation § Requesting temporary lift of IP cap, private IP addresses are not suitable for throttling exceptions:
Please check carefully the IP addresses the conference venue gives you.
If the IP address starts by 10. or by 192.168., this is a private address, used internally on the network, but not routable.
If the IP address is included between 172.16.0.0 and 172.31.255.255, this is also a private address.
Apparently this is not currently enforced in CI; this change with an 172.16.29.137 IP address was merged and deployed, and only afterwards reverted.
I think we should check for private IP addresses in CI rather than hoping that the reviewers or deployers will notice it.